Optimal mechanical design of modular haptic devices

This paper presents two possible mechanical designs for a modular haptic device. In a modular haptic device, each module allows the interaction with a scenario by using a single finger, and by adding more modules, multi-finger interaction can be achieved. In this paper, two different mechanical designs for such haptic modules are presented and compared (4-bar and 5-bar mechanisms). This comparison is performed in terms of inertia, manipulability, workspace width, homogeneity of forces reflection and the resulting direct kinematics and jacobian equations. Moreover, it is described how these modules can be scaled to provide haptic feedback to multiple fingers.